Re: Solids and substances
Originally posted by ProCop
]Oh I see. So it is like a Middle Age discoverer coming to new land: "I declare this land to be a British teritory." That's the way you get vacuum?
And further:
Do you declare 2d space (purely mental concept) to contain vacuum?
Since a volume is merely a continuous set of 2D areas, there is nothing wrong with a flat (Euclidean, not flat because it's 2D!) vacuum area. If area is purely a mental concept, then so is space.
But in reality, space seems to be real.
It seems that vacuum is a mental concept of undiscribable/unexplainable entity (having no possitive qualities - its volume being basically a variable). Vacuum is the old fashioned nothing coated into a scientific term.
Volume is a property. So is curvature. So is energy density, and so forth.
I think the big mental block is the concept of solids and substances here. So let's do a thought experiment. Also note that physics has found that what we perceive as various substances in the form of solids gasses and liquids is merely the result of atoms bonding. You can walk through gas and not solids because of the strength of this. Anyway, to the thought experiment.
Take a volume of say, 10 cubic metres of pure vacuum, and then compare it to a volume of 10 cubic metres of what you would call a solid substance. As they both have the same size, try to define any additional property the substance would have the qualifies it as a substance. If you list the properties of both and compare, you will find that there is no property that could not just as easily add to the vacuum. This is especially true when you recall that atoms are the only thing that gives substances their density. A pure substance, not being made of atoms, would be a different case.
However, if you attempt to give everything a geometric explanation, you'll find that you
can give different volumes differing density, simply by applying the idea that the more curvature in a given volume, the higher it's density.